Mild stroker VS 90mm on stock crank!?

Beezerbob · Post by **Beezerbob** » Fri Dec 26, 2008 11:42 am

What do U think 74 crank on 85.5 pistons vs stock crank with machine in 90mm pistons!? both on stock cam .

which will produce more low RPM torque

perrib · Post by **perrib** » Sat Dec 27, 2008 7:00 pm

74x90.5. Bump it up to 82x90.5. Chines cranks cost the same. It only cost $80 to clearance a case. With the stock cam you could get away with the 84 mm crank and stock length rods.

WestyPop · Post by **WestyPop** » Wed Dec 31, 2008 4:27 am

The late Gene Berg certainly knew what worked. His recommendation for an upright street bus engine, that could have a useful life and good performance, was 78 x90.5. His reasoning was that the weight of the bus is usually making the engine work a lot harder than it would have to in a Bug or Ghia, and that the really huge motors would be under too much stress to last very long.

No surprise, he did recommend dual Webers for the 78 x 90.5 combo, and was running that setup in his own (1969 IIRC) bus. Gene knew, not only from theory, but also lots of experimenting, failure analysis, and extended ownership experience.

Pure race... obviously waaay different than a d/d or camper.

J.R.
68 Westy
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